Safety arrangement



May 16, 1939. F. D. OESTERLE 2,158,635

SAFETY ARRANGEMENT Filed Jan. 8, 1938 5/ FIG. 2.

l l I y l I I 1 l I I nvve/vrop 2a I @143 F. 0. oesrmur A T TORNEV Patented May 16, 1939 UNITED STATES SAFETY ARRANGEMENT Frank D. Oesterle, West Englewood, N. J., assignor to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application January 8, 1938, Serial No. 184,086

6 Claims.

This invention relates to a safety arrangement and more particularly to an organization of means to efiect safety in the operation of a machine tool.

There are various kinds of machine tools which have as a power actuated material working element, a punch, drill, shears, rotary cutter, saw or the like, to which a piece of work is manually presented, or in which a piece of work is manually placed on a support or in a stationary or movable work holder to be operated on by the tool, or in which occasional or periodic access to the tool or work holder when the tool is at rest is desirable.

fit is self evidently highly desirable to provide safety means as accessory to or incorporated in the organization of such machine tools to ensure the operator and particularly the operators hands against contact with the material working element itself while in operation or in motion,

An object of the present invention is to provide safety means in the organization of such a machine tool which shall be simple, durable and effective and which shall interfere as little as possible with the normal operation and functioning of the tool.

With the above and other objects in view one embodiment of the invention may present a machine tcol of the character described having associated therewith or incorporated in the general organization thereof one or more pivotable walls or doors forming in one position a housing substantially enclosing the operating element of the machine, and in another position giving free ac- 3 cess to the element, together with means which coact with the element when the latter is operating to prevent opening of the housing and which coact with the housing when the latter is closed to prevent actuation of the element.

Other objects and features will appear from the following detailed description of one embodiment thereof as applied in the organization of a punch press and taken in connection with the accompanying drawing in which the same refer- 45 ence numerals are applied to identical parts in the several. figures and in which:

Fig. 1 is a partly diagrammatic view in side elevation of a punch press constructed in accordance with the invention;

50 Fig. 2 is a sectional View on the line 2-2 of Fig. 1;

Fig. 3 is a broken detail view of a portion of the ram of the press; and

Fig. 4 is a similar view of a modified form of 55 the ram.

The apparatus herein disclosed comprises a punch press of any appropriate and well known construction which includes a pedestal or support 20 on which is mounted an integral bracket 60 2| and pillar 22, the pillar being vertical and art and forms only the setting for andno part of the present invention, and therefore will not be further described or particularlzed, except to note that in normal operation of the press, work is positioned on the upper face of the die 25 by the hands of the operator to be worked by the punch.

Vertical parallel shafts and 3| are mounted across the C of the bracket 2| parallel to the path of the ram 24. These shafts may conveniently be stationary and stepped at their lower ends in sleeves 32 which are mounted in the bracket 2| and pedestal 20. The upper ends of the sleeves 32 are flush with the inner surface of the bracket 2|. The sleeves 32 may be held in place by set screws 33 and the shafts 3D and 3| press fitted into the sleeves.

Vertical hollow shafts 34 and 35 are mounted on the shafts 3i! and 3| respectively to' be freely rotatable thereon. These rotatable sleeves 34 and 35 abut at their lower ends against and are supported on the upper ends of the sleeves 32.

An eccentric cam, 36 or 31 respectively, is rigidly mounted on each of the shafts or sleeves 34 and 35 near the upper end thereof, as by means of pins 38 and 39 respectively.

Transversely reciprocable sliders, 40 and 4| respectively, are mounted in corresponding slots 46 and 41 in the pillar 22 to be reciprocated by the cams 36 and 31 against compression pumps 42 and 43 housed in the slots and surrounding the a guide pins 44 and 45 of the respective sliders.

The horizontal slots 46 and 4'! partially intersect the vertical path of the ram 24, and each of the sliders is notched at its forward portion, as

clearly shown in Fig. 2, so as to pass the ram.

The rear portion of each slider is too wide to pass the normal cross section of the ram. Preferably the ram will be provided with transverse slots 26 and 21 or notches 28 and 29 as shown in Figs. 3 and 4 respectively, so positioned that, when the ram is in its upper, inoperative position, the broader rear portions of the sliders 4!! and 4| may enter these slots or notches respectively and so look the ram againstmovement;

whereas when the ram is in any other position,

the sliders will be unable to enter the slots or notches.

On each of the rotatable sleeves 34 and 35 is rigidly secured one of two complementary sheet metal housing walls 50 and 5| which are so formed that when they are in the position shown in solid lines in Fig. 2, they form a housing substantially completely enclosing the field of 00- action of a punch carried by the ram 24 with the die 25. The walls 50 and 5| may, however, be swung aside as indicated in dotted lines in Fig. 2 to give ample access to the work field.

The various parts descibed are so proportioned, arranged and related that when the walls 50 and El are in the full line position of Fig. 2, the sliders AG and Al are moved by the springs 42 and 43 to be in their extreme rear positions and thus entirely withdrawn from the slots 26 and 21 or the notches 28 and 29, as the case may be. The ram is thus free to be operated and access is denied to the working field at the die 25.

If the ram be stationary in its uppermost or inoperative position and the doors or walls 50 and 5! be swung apart, as indicated in dotted lines, the cams 36 and 3'! are rotated forcing the sliders ill and M forward to enter the slots 26 and 2? or the notches 28 and 29, as the case may be, and to lock the ram against any downward movement.

If the ram be in any other position than its uppermost, the slots or notches in the ram will be out of register with the sliders, the latter cannot enter the former, the cams 36 and 3'5 and hence the sleeves 34 and 35 cannot be rotated the doors or walls 50 and 5! cannot be opened.

Thus when the housing is open, it mechanic r prevents actuation of the ram 24 and hence or tool carried by the ram. When the housing closed the ram can be actuated and while out of its inoperative position will prevent the housfrom being opened.

While it is thought preferable to provide the ram with the slots or notches to receive the locking sliders, it will be obvious that, if the bottom end of the cam, when the latter is in its uppermost position, rises to or slightly above the level of the line 2-2 of Fig. 1, the slots or notches in the ram may be omitted as the sliders will then extend under the end of the ram to lock it.

ther modifications in and departures from the embodiment herein used to illustrate the invention will readily occur to those skilled in the art and may be made without departing from the spirit and scope of the invention as pointed in and limited solely by the appended claims.

What is claimed is:

1. In a machine tool having a reciprocable material working element, safety means including a safety housing normally enclosing the element and comprising a wall section movable to open the housing, a member reciprocable to lock the element against reciprocation, means actuby the wall section when pivoted to open 1e housing to reciprocate the member to lock eiement, and resilient means to return the member from its element locking position to an lement unlocked position when the wall section is pivoted to close the housing.

In a machine tool having a movable mamiai working element and having a looking n ber formed on the element, safety means including a safety housing normally enclosing the elem nt and comprising a wall section movable to open the housing, a member reciprocable in one direction to engage the locking member and so lock the element against being moved reciprocable in the other direction to be released from engagement with the locking member, a cam driven by the wall section when moved to open the housing to force the reciprocable member into engagement with the locking mem her, and spring means to return the reciprocable member from engagement with the locking member when the wall section is moved to close the housing.

3. In a punch press having a reciprocable ram and having a recess formed in the ram, safety means including a safety housing normally onclosing the path of the working end of the ram and comprising a wall section movable to open the housing, a slider reciprocably mounted in the frame of the press and positioned to be slidable to enter the recess only when the ram is in an inoperative position and so to lock the ram against motion, a cam connected to the movable wall section to drive the slider into the recess when the section is moved to open the housing, and a spring to force the slider out of the recess when the section is moved to close the housing.

4. In a machine tool having a movable material working element, safety means including a safety housing normally enclosing the element and comprising a wall section movable to open the housing, and means actuated by the movable wall section to lock the element against motion when the section is moved to open the housing, the parts being so proportioned and arranged that the element locking means can be actuated by the wall section only when the element is in an inoperative position.

5. In a machine tool having a movable material working element and having a locking member formed on the element, safety means including a safety housing normally enclosing the element and comprising a wall section movable to open the housing, a member reciprocable in one direction to engage the looking member and so look the element against being moved and reciprocable in the other direction to be released from engagement with the locking member, a cam driven by the wall section when moved to open the housing to force the reciprocable member into engagement with the locking member, and spring means to return the reciprocable member from engagement with the locking member when the wall section is moved to close the housing, the parts being so proportioned and arranged that the reciprocable member can be engaged with the locking member only when the element is in an inoperative position.

6. In a machine tool having a movable material working element and having a locking member formed on the element, safety means including a safety housing normally enclosing the element and comprising a wall section movable to open the housing, a member reciprocable in one direction to engage the locking member and so look the element against being moved and reciprocable in the other direction to be released from engagement with the locking member, a cam driven by the wall section when moved to open the housing to force the reciprocable member into engagement with the locking member, and spring means to return the reciprocable member from engagement with the locking member when the wall section is moved to close the housing, the parts being so proportioned and arranged that the movable wall section can be moved to open the housing and to shift the reciprocable member to engage the locking member only when the element is in an inoperative position.

FRANK D. OESTERLE. 

